At present, therapy for treating diseases by interventional catheterization technique is widely applied, and a variety of materials, apparatuses and drugs are placed into the heart, arteries and veins of the human body through this treatment.
When an occluder is placed into the heart, arteries, veins, and left atrial appendage by the catheter interventional method, due to complex anatomical structures of the heart, the artery and vein blood vessels, especially the left atrial appendage, the apparatus is required to be delivered to a predetermined position accurately, and to be well-adapted to the anatomical structure, mechanics requirements and hemodynamics requirements of the predetermined position at the same time. Under the premise of only generating microtrauma to the human body, firstly, the skin near the blood vessel is punctured, a guide wire enters into the blood vessel from the puncturing site, one end of a catheter is delivered to the predetermined position under the guidance of the guide wire, and the other end thereof is reserved in vitro, and then the apparatus is transferred to the predetermined position by using the catheter and a pusher. During such procedure, a fine flexible catheter is required, while the catheter and the guide wire are designed to be visualized under the X ray. Once the catheter reaches the predetermined position, the guide wire is removed, and the apparatus is guided to the tail end of the catheter by using an access established by the catheter through the pusher; when being completely exposed from the tail end of the catheter, the apparatus is released from the pusher.
For example, the occluder is placed into the left atrial appendage by using the catheter interventional method, in order to prevent thrombosis from the left atrial appendage causing atrial fibrillation, and stroke caused by ascending the thrombus to the brain; or in order to prevent systemic embolism caused by the thrombus reaching to other parts of the body through a body blood circulation system. Placing the occluder into the left atrial appendage to occlude the left atrial appendage and block the blood flow entering into the left atrial appendage can eliminate the risk of thrombosis formed in the left atrial appendage, thus preventing stroke. At present, the apparatuses are usually threadedly connected to a delivery sheath.
With reference to FIG. 1 and FIG. 2, FIG. 1 shows an existing left atrial appendage occluder located in an anatomical structure of the heart and the left atrial appendage, and FIG. 2 is a structure diagram of the existing left atrial appendage occluder, wherein 01 means left atrium, 02 means left atrial appendage and 03 means left atrial appendage cavity wall. The occluder includes a sealing disc 11 and a fixing bracket 12 which consists of a plurality of supports 13; a fixing anchor (or referred to as anchoring barb) 15 is arranged on each of the supports 13, and the supports 13 are extended to ball ends of support ends 14 starting from a position where the fixing anchor 15 is located, and spaced from each other; a connecting nut 16 is arranged on the sealing disc 11 of the left atrial appendage occluder. The occluder has good elasticity, may be contained in a sheath with width of 2 to 4 mm, transferred into the left atrial appendage 02 through the vascular access, and slowly retreated from the sheath tube; the fixing bracket 12 of the occluder will be unfolded in the left atrial appendage cavity, and the supports 13 of the fixing bracket 12 will be pressed on the left atrial wall by adapting to the shape of the left atrial appendage 02, while the fixing anchor 15 of the supports 13 will be penetrated into the inner wall 03 of the left atrial appendage, thus guaranteeing reliable fixation, and, the sealing disc 11 is covered on the ostium of the left atrial appendage 02, as shown in FIG. 1. Finally, a steel cable connected to the left atrial appendage occluder is released, thus occluding the left atrial appendage and blocking the blood flow entering into the left atrial appendage.
The above left atrial appendage occluder has the following limitations: the support ends of the fixing bracket are spaced and suspended. When the fixing bracket is pushed out after being placed into the sheath tube, the risk of twisting between the support ends exists, resulting in possible failure of the fixing bracket to unfold properly, and therefore a failed procedure.